1. Field of the Invention
The present invention relates generally to tape head polishing devices and methods, and more particularly to a tape head polishing device and method in which the motion of the polishing medium motion is synchronized with the tape head motion.
2. Description of the Prior Art
Recording heads for tape drives, hereinafter referred to as tape heads, are fabricated on wafer substrates utilizing photolithographic and thin film fabrication techniques, as are well known to those skilled in the art. Following the slicing of the wafers, the sensor head surface of the tape head is generally ground and lapped. A problem that often occurs during this lapping process is that the ductile metal of the magnetic shields of the tape head can be smeared across the insulation layers of the tape head to make contact with the sensor elements of the head, thus creating electrical shorts which will compromise the performance of the device. A tape head polishing step is generally next conducted, typically utilizing a diamond polishing tape or other polishing medium, in an attempt to remove the smears and to provide a final polished surface to the head. However, the prior art tape head polishing process has not been entirely successful in removing the smears, and tape heads are produced having smears that cause electrical shorts which degrade the performance of the tape heads. A need therefore exists for a tape head polishing device and method which will polish the tape head in a manner that substantially removes the smears, such that the problem of electrical shorts in the fabricated tape heads is diminished.
In the tape head polishing method of the present invention the tape head is moved orthogonally to the polishing medium direction of motion during polishing. While the typical polishing medium is a diamond polishing tape, the present invention is not to be so limited; however, for simplicity, the polishing medium shall be inclusively referred to herebelow as a polishing tape. The polishing tape motion is synchronized with the tape head motion, such that the polishing tape is held stationary when the tape head motion is stationary, and the polishing tape is moved when the tape head motion is approximately at a maximum velocity. The tape head velocity VH and the polishing tape velocity VT during the tape motion are generally related by the equation VTxe2x89xa6VH Tan xcfx86, where Tan xcfx86=W/L, where W is the width of an insulation layer fabricated between a magnetic shield and a tape head sensor element, and L is the length of a sensor element.
It is an advantage of the tape head polishing method of the present invention that magnetic shield metalization smears which cause electrical short circuits are substantially eliminated.
It is another advantage of the tape head polishing method of the present invention that tape heads are produced having a higher reliability and lower failure rate.
It is a further advantage of the tape head polishing method of the present invention that a higher throughput of properly functioning tape heads is achieved.
It is yet another advantage of the tape head polishing method of the present invention that the fabrication expense of tape heads is reduced due to the increased throughput of properly operating tape heads.
It is an advantage of the tape heads produced by the polishing method of the present invention that metalization smears are substantially eliminated, such that electrical shorts within such tape heads are reduced.
It is an advantage of the tape head polishing device of the present invention that metalization smears are substantially removed during the tape head polishing process.
These and other features and advantages of the present invention will no doubt become apparent to those skilled in the art upon reading the following detailed description which makes reference to the several figures of the drawings.